1. Field of the Invention
The present invention relates to an image forming device fabrication method and fabrication apparatus using a (surface-conduction type) electron-emitting element.
2. Related Background Art
Conventionally, electron-emitting elements are mainly classified into two types of elements: thermionic and cold cathode electron-emitting elements. Known examples of the cold cathode electron-emitting elements are field emission type electron-emitting elements (to be referred to as FE type electron-emitting elements hereinafter), metal/insulator/metal type electron-emitting elements (to be referred to as MIM type electron-emitting elements hereinafter), and surface-conduction type electron-emitting elements.
Known examples of the FE type electron-emitting elements are disclosed in W. P. Dyke and W. W. Dolan, "Field Emission", Advance in Electron Physics, 8, 89 (1956) and C. A. Spindt, "Physical Properties of Thin-Film Field Emission Cathodes with Molybdenium Cones", J. Appl. Phys., 47, 5248 (1976). A known example of the MIM type electron-emitting elements is disclosed in C. A. Mead, "Operation of Tunnel-Emission Devices", J. Appl. Phys., 32,646 (1961). A known example of the surface-conduction type electron-emitting elements is disclosed in, e.g., M. I. Elinson, Radio Eng. Electron Phys., 10, 1290 (1965).
The surface-conduction type electron-emitting element utilizes the phenomenon that electrons are emitted from a small-area thin film formed on a substrate by flowing a current parallel through the film surface. The surface-conduction type electron-emitting element includes electron-emitting elements using an SnO.sub.2 thin film according to Elinson mentioned above [M. I. Elinson, Radio Eng. Electron Phys., 10, 1290, (1965)], an Au thin film [G. Dittmer, "Thin Solid Films", 9,317 (1972)], an In.sub.2 O.sub.3 /SnO.sub.2 thin film [M. Hartwell and C. G. Fonstad, "IEEE Trans. ED Conf.", 519 (1975)], a carbon thin film [Hisashi Araki et al., "Vacuum", Vol. 26, No. 1, p. 22 (1983)], and the like.
Since the surface-conduction type electron-emitting elements have a simple structure and can be easily fabricated, many elements can be formed on a wide area. Various applications using this feature have been studied. For example, surface-conduction type electron-emitting elements are applied to charged beam sources, display devices, and the like. An example using a large number of surface-conduction type electron-emitting elements is an electron source formed by arranging many rows prepared by arranging surface-conduction type electron-emitting elements parallel and connecting them at the two terminals of each element with a wiring line (to be also referred to as a common wiring line) (e.g., Japanese Patent Application Laid-Open Nos. 64-031332, 1-283749, and 2-257552).
On the other hand, flat display devices using liquid crystals have recently replacing CRTs in image forming devices such as display devices. The flat display devices undesirably require a backlight because they are not of a self-emission type. Demands arise for development of self-emission type display devices. An example of the self-emission type display devices is an image forming device as a display device using a combination of an electron source formed by arranging a large number of surface-conduction type electron-emitting elements and a fluorescent substance which emits visible light upon reception of electrons emitted by the electron source (e.g., U.S. Pat. No. 5,066,883).
FIG. 28 shows an example of a method of fabricating a conventional flat image forming device. After an electron source substrate and luminescent display plate are formed, an area defined between the electron source substrate and luminescent display plate is evacuated upon an assembling step. If necessary, baking is done as a degassing step, and sealing and getter flash steps are done to fabricate an image forming device.